I. Field of the Invention
The present invention relates to an article of manufacture having a powdered metal part which is mechanically secured to a second part by mechanical deformation of a lip on the first part.
II. Description of the Prior Art
Components manufactured from powdered metal have enjoyed increased popularity in industry for a number of reasons. One principle reason, however, is that complex shapes can be relatively inexpensively manufactured with powdered metal components as opposed to machining the component from standard metals. Furthermore, powdered metal components minimize the amount wastage of material in sharp contrast to machining operations of conventional metal.
Even though powdered metal components can be manufactured in complex configurations, in many situations it is necessary to mechanically secure a powdered metal part to a second part, typically constituted of standard metal. For example, in automotive applications, the main body of a pulley is oftentimes constructed from powdered metal. Thereafter, an annular belt retainer constructed from a metal stamping must be secured to one end of the main body. Furthermore, due to the shape of the main body when assembled to the belt retainer, it is not possible to manufacture the belt retainer and main body as a single powdered metal component.
There have been several different previously known ways for mechanically securing a powdered metal part to a non-powdered metal part. One such method has been to weld the parts together. This method, however, is only effective where the powdered metal part, or at least the portion which is to be welded to the other part, has a low carbon content. Otherwise, the carbon content of the powdered metal part precludes welding the parts together.
Still a further method of securing the powdered metal part and non-powdered metal part together has been to assemble the part together and then stake the junction in between the parts. In doing so, the deformation of the non-powdered metal part caused by the staking operation attaches the parts together. Such staking, however, creates a relatively weak mechanical bond between the powdered metal and non-powdered metal part so that even a relatively axial force between the parts is sufficient to separate them. This is particularly true for large components.